howopentimestampscarbornalmosttheentirewebwithonebitcointx

The OpenTimestamps team has timestamped every item in the Internet Archive –
about 750,000,000 files in total – and made those timestamps publicly
available via a searchable
database.
Let’s look at an example attack on the archive, how a timestamp could prevent
it, and finally, the tech details behind this effort.
The OpenTimestamps proofs we’ve generated are
traceable back to the Bitcoin blockchain, a widely witnessed data structure with
timestamps that can’t be backdated.
Generating the Merkle Tree

There have been a lot of ridiculously inefficient Bitcoin timestamping schemes,
using one, or even
two
Bitcoin transactions per timestamp.
Web Captures